The “Superworld” is a subject of formidable interest for the immediate future of subnuclear physics to which Zichichi has contributed with a series of important papers of phenomenological and theoretical nature. These papers represent a must-have collection, not only for their originality but also for their complete analysis of expected scenarios on the basis of today's knowledge of physics.The contributions are divided into two parts. The first deals with the problem of the convergence of the three fundamental forces of nature measured by the gauge couplings, with the onset of the energy threshold for the production of the lightest supersymmetric particles and with the existence of a gap between the string scale and the GUT scale. The second deals with the study of a theoretical model capable of including supersymmetry with the minimum number of parameters (possibly one), and agreeing with all the conditions established by string theories — this turns out to be a “one-parameter no-scale supergravity” model whose experimental consequences are investigated for present and future facilities aimed at the discovery of the first example of the superparticle.Sergio Ferrara and Michael Duff, two of the founders of supergravity, superstring and M-theories, introduce the fascinating subject of supersymmetry, superspace and the superworld; the presentation of the seminal papers by Zichichi and his collaborators is made by two eminent physicists: Rudolf Mössbauer and Sergio Ferrara.